Need help picking out a video card

So I got a new computer for Christmas and it doesn’t have an HDMI out so I want to add one. Can anyone recommend a video card? I have a 50" Panasonic Plasma I want to hook it up to for occasional videos off of the internet and off the Hard Drive. It will be used for minimal HTPC functions. I would like it to have 2 outputs too, 1 for the TV and one for my monitor so I can just leave them both hooked up. The monitor is a VGA cable. Here are the available ports:
PCI One (One available)
PCI Express x16 One (One available)
PCI Express x1 Two (One available)

Here’s a link to the actual machine if it helps.
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c02575965〈=en&cc=us&taskId=120&contentType=SupportFAQ&prodSeriesId=4269976&prodTypeId=12454

to run a decent gfx card you’d need to upgrade the psu. Not sure on case design but i believe a 9600gt or gts450 should get you where you wanna be with what you have. Wait for others to chime in though.

it doesn’t sound like you need much you should be able to get a low end card, and keep your current power supply as long as you don’t want to game.

this should do what you want. http://www.newegg.com/Product/Product.aspx?Item=N82E16814102896

I know how HDMI works but it looks like on some cards the audio doesn’t come through the HDMI. How can I tell if it definitely does? Or do they pretty much all come through the HDMI now? The stuff I was reading was like a year old so I don’t know if that’s since changed to be standard.